Page:Transactions of the Linnean Society of London, Volume 12.djvu/107

Rh my observations as either wholly or even in any considerable degree anticipated by the passage in question. My observations notice not only the disposition of the five vessels in the tube of the corolla, but their ramification in the laciniæ, by no means a necessary consequence of that disposition; they notice also the existence, in several genera of Compositæ, of five vessels alternating with those, and which I considered secondary in this order, though they occupy the place of the primary vessels in other families: and it is this inverted disposition, indicated in the greater part of the class by the primary being the only vessels existing, which I have considered as of material importance in determining the limits of Compositæ, though by no means as affording an essential practical character for the whole class.

In the passage quoted from M. Cassini (the only one I can find relative to the subject in the memoir in which it occurs), the existence of five nerves or vessels in the tube of the corolla, alternating with its laciniæ, is stated, but their division and disposition in the laciniae are not noticed; it is at the same time to be inferred from the terms of the passage, that no other vessels exist in the tube of the corolla: and it is equally evident that, so far from announcing this disposition of vessels as a discovery, or peculiar to the order, the author rather considers it either as a fact already known, or as the usual structure. That M. Cassini was not then aware of the importance of the fact which he had imperfectly stated, appears likewise from his having, many months after his memoir was read, and at a time when he says he had finished his analysis of the corolla, proposed a name for the class, taken from a supposed peculiarity in the structure of the filament, a name which he is now inclined to abandon for one derived from the disposition of vessels in the corolla.

Since